• Carbon letters
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• 제2권1호
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• pp.44-54
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• 2001

The characteristics of adsorption and desorption of benzene and toluene were investigated at a fixed bed packed with the activated carbon and activated carbon fiber. Through breakthrough experiments under various feed concentration conditions, it was found that the slope of mass transfer zone and the tailing in the breakthrough curves were different from the feed conditions due to different heats of adsorption. In hot nitrogen desorption, the regeneration time and mass transfer zone of the toluene desorption curve were longer than those of the benzene desorption curve because of the difference in adsorption affinity. With an increase in the regeneration temperature, the height of roll-up and the sharpness of desorption curves increased but the regeneration times decreased. The adsorption capacities of the activated carbon and activated carbon fiber after three-time thermal regenerations decreased about 25% and 37% for benzene and 18% and 25% for toluene, respectively. To investigate the effect of the regeneration temperature on the energetic efficiency, the characteristic desorption temperatures of toluene and benzene were investigated by calculating purge gas consumption and temperature.

• Current Applied Physics
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• 제18권12호
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• pp.1600-1604
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• 2018

This paper reports on a systematic and quantitative assessment of light induced degradation (LID) and regeneration in full Al-BSF and passivated emitter rear contact cells (PERC) along with the fundamental understanding of the difference between the two. After LID, PERC cells showed a much greater loss in cell efficiency than full Al-BSF cells (~0.9% vs ~0.6%) because the degradation in bulk lifetime also erodes the benefit of superior BSRV in PERC cells. Three main regeneration conditions involving the combination of heat and light ($75^{\circ}C/1\;Sun/48h$, $130^{\circ}C/2\;Suns/1.5h$ and $200^{\circ}C/3\;Suns/30s$) were implemented to eliminate LID loss due to BO defects. Low temperature/long time ($75^{\circ}C/48h$) and high temperature/short time ($200^{\circ}C/30s$) regeneration process was unable to reach 100% stabilization. The intermediate temperature/time ($130^{\circ}C/1.5h$) generation achieved nearly full recovery and stabilization (over 99%) for both full Al-BSF and PERC cells. We discussed the effect of temperature, time and suns in regeneration mechanism for two cells.

• 청정기술
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• 제16권4호
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• pp.272-276
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• 2010

이소프렌(isoprene)에 포함되어 있는 acetylene류의 불순물 중 2-butyne을 선택적으로 제거하기 위해 제올라이트를 흡착제로 사용한 흡착 및 탈착 특성을 연구하였다. 본 연구에서는 제올라이트 5A를 사용하여 흡착실험을 실시한 후, 흡착제를 재생하기 위한 탈착실험을 수행하여 2-butyne의 재흡착 성능을 확인하였다. 감압 및 고온의 질소 가스를 이용한 탈착실험에서 온도 영향과 탈착 시간에 따른 변화를 검토하고 재흡착실험을 실시하였으며 에너지 소비를 최소화하며 흡착성능을 유지할 수 있는 탈착조건을 확립하였다. 473 K, 16시간 탈착 및 액상흡착 반복실험을 10회 진행하여 흡착제의 재생가능성을 확인하였다.

• 한국약용작물학회지
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• 제14권2호
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• pp.87-91
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• 2006

An efficient plant regeneration of C. asiatica was achieved from organogenesis using petiole explants of in vitro plantlet on MS basal medium controled with different plant growth regulators (NAA,2,4-D, IAA kinetin, and BA). Best results that 50%, efficiency of regeneration per explant for regeneration were obtained with IAA $17.13\;{\mu}M$ and BA $8.9\;{\mu}M$. Formation of adventitious shoots via organogenesis from the petiole explant was verified by histological sectioning of plantlets. Regenerated plants were transplanted into soil.

• 상하수도학회지
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• 제23권4호
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• pp.407-416
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• 2009

The objective of this study was to evaluate the variation of physical properties and adsorption capacity after regeneration of Granular Activated Carbon (GAC). It was found that the loss rate of regenerated carbon was related to the usage time of GAC. The correlations between iodide number and loss rate also determined. Effective size and uniformity coefficient for regenerated GAC were within a similar range compared to virgin GAC. This result indicated that the function as media is recovered. Although iodide number and specific surface area for regenerated GAC were not completely recovered compared to that of virgin GAC, cumulative pore volumes of regenerated GAC were increased. Removal efficiency of organic matter in regenerated GAC was resulted the same or slightly higher than that of virgin GAC. This result indicates that the number of mesopore responsible for removal of organic matter was increased after regeneration.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.817-824
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• 2002

Granular activated carbon(GAC) is highly effective in removing organic compounds which are resistant to biological disintegration in wastewater treatment. However, GAC has reached its full adsorptive capacity, GAC needs to be regenerated before it can be used for a further adsorption cycle. Countercurrent oxidative reaction (COR) technique has been developed and evaluated for the regeneration of spent GAC. Various parameters such as flame temperature, the loss of carbon, destruction and removal efficiency (DRE) of organic compounds, surface area, surface structure, adsorptive capacity, etc. were examined to determine the performance of COR. The results of these tests showed that adosorptive capacity of regenerated GAC was completely recovered, the loss of carbon was controllable, flame temperature was high enough to insure complete destruction and removal $(\geq99.9999%)$ of specific organics of interest, polychlorinated biphenyls (PCBs), that are thermally stable, and on formation of toxic byproducts such as polychlorinated dibenzo-p-dioxins (PCDDs) or polychlorinated dibenzofurans (PCDFs) were detected during the regeneration process. The COR technique is environmentally benign, easy to use and less copital intensive than other available regeneration technologies.

• 생명과학회지
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• 제17권6호통권86호
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• pp.822-824
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• 2007

KN배지에서 상추 자엽과 제1엽 절편체로부터 식물체 재분화율을 품종별 비교 했을 때, 자엽에서 정통포기 품종이 91.3%로 가장 높게 나타났고, 고향뚝적축면 품종이 52.3%, 청치마 품종이 35.4%로 가장 낮게 나타났다. 제1엽에서도 정통포기 품종이 85.9%로 가장 높게 나타났고, 고향뚝적축면품종이 50.8%, 청치마 품종에서 30.3% 효운을 나타내었다. 재분화 효율이 가장 낮은 청치마 품종의 재분화 효율을 높이기 위해 다양한 재분화 배지를 사용하여 청치마 품종의 자엽과 제1엽의 식물체 재분화 효율을 비교했다. 자엽에서 재분화 효율은 Kl 배지와 SH 배지, NB 배지에서 거의 평균 77.2%의 높은 재분화 효율을 나타내었고, MSD3 배지에서는 그 보다 낮은 61.1%의 효율을 나타내어 모든 배지에서 KN배지 보다 높게 나타났다. 제1엽에서도 SH 배지에서 85.0%로 가장 높게 나타났고, Kl 배지에서 80.7%, NB 배지에서 67.4%, MSD$_3$배지에서 61.0%의 효율을 나타내어 KN배지보다 모두 높게 나타났다. 따라서 본 실험의 결과 상추의 자엽과 제 1엽 절편체들로부터 효율적인 재분화는 정통포기 품종의 자엽을 K띠 배지에 배양했을 때 가장 효율적으로 나타났으며, 청치마 품종에서는 제 1엽을 SH 배지와 Kl 배지에 배양했을 때 재분화가 효율적인 것으로 나타났다.

• 한국초지조사료학회지
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• 제20권4호
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• pp.259-264
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• 2000

오차드그래스의 완숙 종자배양에서 배지 내에 첨가되는 copper의 농도가 캘러스 형성과 식물체 재분화율에 미치는 영향을 조사하였다. 캘러스의 유도는 $2\;mg/{\ell}$의 2,4-D와 $0.1-100\;{\mu}mol$의 copper sulfate를 첨가한 MS 배지를 이용하였으며, 식물체 재분화는 $1\;mg/{\ell}$의 NAA, $5\;mg/{\ell}$의 kinetin 및 $0.1-100\;{\mu}mol$의 copper sulfate가 첨가된 N6 배지를 이용하였다.그 결과, copper의 첨가는 캘러스 형성능력에는 유의성있는 차이를 나타내지 않았으나, copper가 첨가된 배지에서 생성된 캘러스에서 백색이면서 조직이 치밀한 즉, 식물체 재분화에 적합한 캘러스의 비율이 높게 나타났다. 식물체 재분화율은 copper가 첨가된 배지에서 생성된 캘러스가 첨가되지 않은 배지에서 생성된 캘러스보다 높게 나타났으며, 특히 $70\;{\mu}mol$의 copper가 첨가된 백지에서 생성된 캘러스가 대구조에 비해 2.5배 이상 증가된 가장 높은 재분화 능력을 나타내었다. 또한, 캘러스당 재분화된 식물체의 수는 $70\;{\mu}mol$의 copper가 첨가된 배지에서 생성된 캘러스에서 대조구에 비해 2.6배 이상 증가된 것으로 나타났다.

• Journal of Plant Biotechnology
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• 제36권4호
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• pp.373-383
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• 2009

To set efficient transformation system in chrysanthemum, thirty-four chrysanthemum (Dendranthema grandiflorum Kitamura) varieties were collected and cultured for shoot regeneration. Five varieties, ‘Shuho-no-chikara', ‘Zinba', ‘Baekma', ‘Pink pride' and ‘Keumsu' of them were selected, because they had a high shoot regeneration efficiency. MS medium containing 1.0 mg/L NAA and BA respectively was very adequate for shoot regeneration in those varieties. MS medium with 3.0 mg/L NAA and 1.0 mg/L kinetin in ‘Shuho-no-chikara' and the medium with 0.5 mg/L NAA and 3.0 mg/L BA in ‘Keumsu' were also suitable for shoot regeneration. The most efficient callus induction and shoot regeneration were obtained on MS medium. Shoot regeneration was enhanced more than 8% on MS medium with 0.3% phytagel and 10-15 mg/L putrescine. The best cultural material for shoot regeneration was stem. When stem was used as a culture material, shoot regeneration rate was increased more than 26% and the days to shoot regeneration was shortened about 14 days.

• 대한환경공학회지
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• 제22권2호
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• pp.291-302
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• 2000

연료가스로부터 황화수소를 제거하기 위해 망간계 탈황제를 개발하여, 대기압하 고정층반응기에서 황화/재생 반복실험을 통하여 탈황제의 효용성, breakthrough times, 그리고 평형농도를 구하였다. 황화수소 제거능에 영향을 미치는 입자크기, 황화반응 온도, 재생온도 그리고 재생 특성에 관해 살펴보았다. 황화수소 제거를 위한 적정 조업온도는 $800^{\circ}C$였으며 입자크기가 감소할수록 탈황능은 증가하였으나 입경 0.214~0.631mm에서는 큰 차이를 보이지 않았다. 실험으로부터 구한 황화수소 평형관계식은 log(K)=3.396/T-1.1105이고 탈황제 이용효율은 $800^{\circ}C$에서 92%를 나타냈다. 공기를 사용해서 재생할 때 $SO_2$ 배출농도는 $800^{\circ}C$에서 8.5% 이상, $850^{\circ}C$에서 8.4% 이상, 그리고 $900^{\circ}C$에서 8.8% 이상을 보여 황산제조에 사용될 수 있을 것으로 판단된다.